<?php
$numbers = [1, 2, 3, 4, 5];

print_r(array_sum($numbers));// 15

print_r(array_product($numbers));// 120

print_r(array_reduce($numbers, function ($carry, $item) {
    return $carry ? $carry / $item : 1;
}));// 0.0083 = 1/2/3/4/5

print_r(array_reduce($numbers, function ($carry, $item) {
    echo $carry ? "{$carry}-{$item}\n" : '';
    return $carry ? $carry - $item : $item;
}, 0));// 1-2-3-4-5 = -13

class aaa implements LoggerInterface {

}